Bought carbs but they don't have air mixture screws. What the...?

[zblip2]

Just bought a set of carbs on ebay and they don't have air mixture screws. I meen, where there should be screws there is some sort of factory cap that looks like a screw head but is just flat with nothing for a screw driver to hold on to. How does one adjust his carbs with this type of air mixture system???

[Billy Ricks]

Just bought a set of carbs on ebay and they don't have air mixture screws. I meen, where there should be screws there is some sort of factory cap that looks like a screw head but is just flat with nothing for a screw driver to hold on to. How does one adjust his carbs with this type of air mixture system???

You have to drill the caps over the mixture screws the insert a screw and pull the caps off. Be careful and don't let the drill bit plunge into the bore the screw is in or you can ruin the threads. Use some tape on the bit to limit how far the bit goes in. 1/8" should be plenty of depth.

[zblip2]

You have to drill the caps over the mixture screws the insert a screw and pull the caps off. Be careful and don't let the drill bit plunge into the bore the screw is in or you can ruin the threads. Use some tape on the bit to limit how far the bit goes in. 1/8" should be plenty of depth.

Thanks for the answer but what exactly do you meen by "insert a screw and pull the caps off"? Is there an air mixture screw underneath the cap?

Thanks

[Billy Ricks]

Thanks for the answer but what exactly do you meen by "insert a screw and pull the caps off"? Is there an air mixture screw underneath the cap?

Thanks

It's under the cap. You drill a hole first then insert a screw to pull it out with pliers or vice grips. The carb cleanup series on the homepage gives details.

[zathros]

Use a sheet metal screw, as you tighten the screw, it will bite in and the plug will start to spin and out it will come. Use some WD or other lubricant as these plugs may oxidize a bit. Make sure that your screw driver fits the mixture screw exactly or you will strip the heads. This happens more often than not and you will then have a handful of work to do.

[zblip2]

Now I get it!

Thanks guys!

[oldgsfan]

BTW, I just did this very thing last week.
After I got the caps off, I ended up damaging the screws themselves without hardly trying just getting them out.

Mine were a real bitch to get out.

You'll know the threads are messed up 'cause they won't screw in like you need them to. Anyway, point is I ordered some new ones from Z1Enterprises at $8.55 a piece. It was worth it.

Just fyi.

[zathros]

@Oldgsfan, How did you get them out? I may attempt this in the winter (or future) I am lucky as my bike is running fine but who knows. My striped when I looked at them. Very weak.

[scrapper]

I had a bad adjustment screw in my bike that is one reason I put carb kits in it, float valves were leaking by, also needed new bowl gaskets, I got the kits on ebay from georgefix. I couldn't get the air screw to back out so I drilled it and used a easy out, got them from sears. I think it was around 5.00 to 6.00 bucks for the drill bit and the easy out.I got 2 drill bits just incase.It worked good.

[schlyme]

Just bought a set of carbs on ebay and they don't have air mixture screws. I meen, where there should be screws there is some sort of factory cap that looks like a screw head but is just flat with nothing for a screw driver to hold on to. How does one adjust his carbs with this type of air mixture system???

the caps where put there in the factory because of epa rules to reduce pollution. if your gonna mess with the idle mixture you may want to get a colortune( i think thats how its spelled) to get your mixture right. as far as pulling the caps, i think the rest of the guys have covered it well enough. plus my carbs already had there caps pull when i got my bike